Powerboat

ABSTRACT

A powerboat includes a hull, a driving mechanism, which is formed of an engine and a driveshaft and is mounted inside the hull around the connection area between the bottom and transom of the hull, a shield fastened to the transom outside the hull and defining a semicircular waterway, a guide wing affixed to the bottom side of the shield, and a propeller unit, which is installed in the rear side of the shield and affixed to the guide wing and which has a front propeller coupled to the driveshaft, a rear rudder, and a vane wheel set between the propeller and the rudder.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a powerboat and more particularly to such a powerboat, which is easy to assemble and has a broad internal space for use.

2. Description of the Related Art

A conventional powerboat 80, as shown in FIG. 4, comprises a hull 81, an engine 82, a propeller 83, and a rudder 84. The engine 82 is adapted to drive a driveshaft 86, causing the driveshaft 86 to rotate the propeller 83. The rudder 84 is controlled by a steering gear 87 to control the steering direction of the powerboat 80. As shown in FIG. 4, the engine 82 is mounted inside the hull 81 near the center, therefore the inside space of the hull 81 around the center area cannot be used for other purposes, i.e., the utilization of the inside space of the powerboat 80 is reduced. Further, because the driveshaft 86 is obliquely mounted in the bottom of the hull 81, the propeller 83 and the driveshaft 86 may hit or stick in a terrace or rocks in shoals accidentally. Therefore, this design of powerboat 80 is suitable for use in a deep draught area only.

FIG. 5 shows a jet boat according to the prior art. According to this design, the jet boat 90 comprises a hull 91, an engine 92, and a jet propeller 93. The hull 91 of the jet boat 90 has a semicircular recess disposed at the bottom side and covered with a covering molded from FRP (Fiber Reinforced Plastics) to form a semicircular waterway 94. The jet propeller 93 is mounted in the semicircular waterway 94. The engine 92 is mounted in the center area inside the hull 91, which limits the utilization of the internal space of the jet boat 90. Further, the design of the semicircular recess at the bottom side of the hull 91 greatly complicates the processing process of the jet boat 90, thereby increasing the manufacturing cost. Further, because this design of jet boat 90 uses a jet propeller, it is suitable for use in a place where the water is shallow. However, due to low water intake amount, when used in shoal water, the jet propeller of this design of jet boat is suitable for use at a high speed and high pressure. During a low speed operation, the efficiency of the jet propeller becomes low.

Therefore, it is desirable to provide a powerboat that eliminates the aforesaid drawbacks.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a powerboat, which keeps thee hull in unity, increasing the utilization of the internal boat space.

It is another object of the present invention to provide a powerboat, which is easy to assemble.

To achieve these objects of the present invention, the powerboat comprises a hull having a bottom and a transom, and a driving mechanism mounted inside the hull around a connection area between the bottom and transom of the hull. The driving mechanism includes an engine and a driveshaft rotatable by the engine. A shield is fastened to the transom outside the hull and defines a semicircular waterway therein. A guide wing is affixed to a bottom side of the shield. A propeller unit is installed in a rear side of the shield and affixed to the guide wing. The propeller unit has a propeller disposed at a front side thereof and coupled to the driveshaft, a rudder disposed at a rear side thereof, and a vane wheel set between the propeller and the rudder.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional side view of a part of a powerboat according to a first preferred embodiment of the present invention.

FIG. 2 is a rear side view of the powerboat according to the first preferred embodiment of the present invention.

FIG. 3 is a rear side view of a powerboat according to a second preferred embodiment of the present invention.

FIG. 4 is a side view of a powerboat according to the prior art.

FIG. 5 is a schematic drawing of another structure of powerboat according to the prior art.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1 and 2, a powerboat 10 in accordance with the first preferred embodiment of the present invention is shown comprising a hull 11, a driving mechanism 21, a shield 31, a guide wing 32, and a propeller unit 41.

The hull 11 is the body shell of the powerboat 10, preferably molded from FRP (Fiber Reinforced Plastics) or made of aluminum alloy, having a bottom 12 and a transom 14. The hull 11 has a through hole 16 cut through the transom 14. The through hole 16 is mounted with a thrust bearing 18 and a water-tight gasket 19.

The driving mechanism 21 comprises an engine 22, a driveshaft 24, and a sleeve 26. The engine 22 is mounted inside the hull 11 adjacent to the connection area between the bottom 12 and the transom 14 for providing the necessary driving force to move the powerboat. Because the engine 22 is mounted inside the hull 11 adjacent to the connection area between the bottom 12 and the transom 14, the hull 11 provides a big internal space, more particularly, the center space for use. The driveshaft 24 extends outwards from the engine 22 to the outside of the hull 11 and is supported in the thrust bearing 18. The driveshaft 24 according to this embodiment is comprised of two parts connected in line by a universal joint 25. The sleeve 26 is sleeved onto the driveshaft 24 and affixed to the thrust bearing 18 outside the hull 11. According to this embodiment, the hull 11 needs only to be provided with the through hole 16 for the passing of the driveshaft 24 of the driving mechanism 21.

The shield 31 defines a semicircular waterway, having a semicircular front mounting board 34 affixed to the transom 14 of the hull 11 with screws 311 and a plurality of reinforcing ribs (for example, two reinforcing ribs) 36 extended from the semicircular front mounting board 34 around the semicircular waterway to reinforce the structural strength of the shield 31.

The guide wing 32 is a flat member fastened to the periphery of the sleeve 26 below the shield 31.

The propeller unit 41 is connected to the rear side of the shield 31 and joined to the guide wing 32. Because the propeller unit 41 is fastened to the rear side of the shield 31 and the guide wing 32, it is stable. The propeller unit 41 comprises a propeller 42, a vane wheel 44, and a rudder 46. The propeller 42 is disposed at the front side of the propeller unit 41 and rotatable by the driveshaft 24 to provide a propelling force. The vane wheel 44 is disposed at the rear side of the propeller 42. The rudder 46 is disposed at the rear side of the propeller unit 41.

Further, a simple linking mechanism 50 is provided to link the rudder 46 to the cockpit of the powerboat 10 so that the pilot can bias the rudder 46 conveniently.

Compared with conventional powerboats, the invention has the following advantages:

1. By means of suspending the shield 31 and the propeller unit 41 on the outside of the hull 11, the hull 11 is maintained in whole, and hull 11 needs only to provide a through hole 16 for the passing of the driveshaft 24 of the driving mechanism 21. Further, because the engine 22 is mounted inside the hull 11 adjacent to the connection area between the bottom 12 and the transom 14, the hull 11 provides a big internal space for use.

2. The guide wing 32 provides a support to the propeller unit 41 to hold the propeller unit 41 firmly in place, and blocks external objects from passing to the waterway of the shield 31 during operation of the propeller unit 41.

3. Because the tilting angle of the shield 31 and the propeller unit 41 is relatively smaller when compared with the prior art designs, the propeller 42 is kept in a position close to vertical, the powerboat 10 is free from the limitation of draught.

4. Compared with the prior art designs, the powerboat of the invention has a simple structure and is easy, and expensive to manufacture. Therefore, the invention has an industrial value.

Further, the mounting location or the number of the shield and the propeller unit may be changed without departing from the spirit and scope of the invention. FIG. 3 shows an alternate form of the present invention. According to this embodiment, the powerboat 60 has two shields 64 and two propeller units 66 symmetrically mounted in the hull 61 on the outside to provide a high propelling force. 

1. A powerboat comprising: a hull having a bottom and a transom; a driving mechanism mounted inside said hull around a connection area between the bottom and transom of said hull, said driving mechanism having an engine and a driveshaft rotatable by said engine; a shield fastened to said transom outside said hull, said shield defining a semicircular waterway; a guide wing affixed to a bottom side of said shield; and a propeller unit installed in a rear side of said shield and affixed to said guide wing, said propeller unit having a propeller disposed at a front side thereof and coupled to said driveshaft, a rudder disposed at a rear side thereof, and a vane wheel set between said propeller and said rudder.
 2. The powerboat as claimed in claim 1, wherein said shield has a mounting board affixed to said transom of said hull.
 3. The powerboat as claimed in claim 2, wherein said shield has a plurality of reinforcing ribs extending from said mounting board around said semicircular waterway.
 4. The powerboat as claimed in claim 1, wherein said driveshaft has a part extended out of said transom and sleeved with a sleeve; said guide wing is affixed to said sleeve at a lower side relative to said shield.
 5. The powerboat as claimed in claim 1, further comprising two said shields affixed respectively to said hull and spaced away from each other, and two said propeller units respectively installed in said two shields. 